• Title/Summary/Keyword: Growth

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Hormonal Regulation of Insulin-Like Growth Factor Binding Protein Secretion by a Bovine Mammary Epithelial Cell Line

  • Kim, W.Y.;Chow, J.C.;Hanigan, M.D.;Calvert, C.C.;Ha, J.K.;Baldwin, R.L.
    • Asian-Australasian Journal of Animal Sciences
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    • v.10 no.2
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    • pp.233-239
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    • 1997
  • A mammary epithelial cell line (MAC-T) established as a model for lactation was utilized to identify and characterize effects of various hormones upon insulin-like growth factor binding protein secretion. Ligand and immunoblot analyses of conditioned media indicated that insulin-like growth factor binding protein-2 was secreted by MAC-T cells. Insulin-like growth factor-I stimulated insulin-like growth factor binding protein-2 secretion in a dose-dependent manner, but prolactin and bovine somatotropin did not alter insulin-like growth factor binding protein-2 secretion. Insulin increased and cortisol decreased insulin-like growth factor binding protein-2 secretion. Effects of insulin-like growth factor-I on insulin-like growth factor binding protein-2 secretion support previous studies using primary cultures of bovine mammary cells and bovine fibroblasts. Effects of cortisol and insulin on insulin-like growth factor binding protein-2 secretion may be explained by changes in protein synthesis. In addition, supraphysiological doses of insulin can cross-react with the insulin-like growth factor-I receptor and stimulate insulin-like growth factor binding protein-2 secretion. MAC-T cells provide a model system to study mechanisms that regulate local insulin-like growth factor-I bioactivity.

AN EXPERIMENTAL STUDY ON THE STIMULATORY EFFECTS OF EPIDERMAL GROWTH FACTOR AND TRANSFORMING GROWTH FACTOR-α ON THE GROWTH OF SQUAMOUS CANCER CELL LINES (Epidermal Growth Factor 와 Transforming Growth Factor-α가 인체 구강편평상피세포암 세포의 성장에 미치는 영향에 관한 실험적 연구)

  • Park, Young-Wook
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.20 no.4
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    • pp.334-340
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    • 1998
  • Stimulatory effects of epidermal growth factor (EGF) and transforming growth $factor-{\alpha}$($TGF-{\alpha}$) on the growth of squamous cancer cell lines established from human oral cancer tissue with moderate differentiation were studied in vitro. After culturing in serum-free media for 24 hours, growth factors-EGF only, $TGF-{\alpha}$ only and EGF, $TGF-{\alpha}$ together-were added to the media and numbers of cells were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and compared with the control at 96, 144 hours. Each of EGF and $TGF-{\alpha}$ showed statistically significant stimulatory effects on the growth of cells respectively. Dose-dependent relationship of the stimulatory effects were not clearly demonstrated. The effects of EGF were higher than those of $TGF-{\alpha}$ and combinative administration showed higher effects than those of single uses. In conclusion, EGF may play an important and major role in differentiation and growth of human oral squamous cancer cells. $TGF-{\alpha}$, produced from cells activated by EGF, also can stimulate the cell growth and could be an alternative ligand for EGF receptor.

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A Study on the Morpholgies and Mechanical Properties of Sn-Zn Eutectic Alloys (Sn-Zn 공정합금(共晶合金)의 응고속도(凝固速度)에 따른 조직(組織)과 기계적(機械的) 성질(性質)에 관한 연구(硏究))

  • Lee, J.H.;Lee, K.W.
    • Journal of Korea Foundry Society
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    • v.5 no.4
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    • pp.258-270
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    • 1985
  • The structures and mechanical properties of undirectionally solidified Sn-Zn eutectic alloys have been examined over the growth range 7mm/h to 6,000mm/h. The structures of unidirectionally solidified Sn-Zn eutectic alloys were primarily broken-lamellar at growth rates below 760mm/h and became fibrous at higher growth rates above that. At a growth rate 3,084mm/h the structures were fibrouse only. There is no dendrites at any growth rates, but occasionally ribbon-like morphologies were seen. The under cooling increased parabolically with growth rate increase. The hardness of specimes increased with growth rates increase but heat-treated specimen decreased after growth rates 760mm/h and became constant value. The effect of heat-treatment was good at lower growth rate. At room temperature tensile strength increased with growth rates up to R=990mm/h and then tensile strength became near-constant value. The effect of heat-treatment was well at lower growth rate.

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A Study of Vision Algorithm Development for Growth Monitoring of Potato Microtubers (인공씨감자 생육상태 모니터링을 위한 화상처리 알고리즘 개발에 관한 연구)

  • Choi, J.W.;Chung, G.J.;Lim, S.J.;Choi, S.L.;Chung, H.;Nam, H.W.
    • Journal of Biosystems Engineering
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    • v.23 no.4
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    • pp.373-380
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    • 1998
  • The contribution of this paper is to provide the methods for the production automation of potato microtuber using the vision process in growth monitoring. The first method deals with computation for the growth density in the primary growth process. The second method addresses cognition process to identify the number and the volume of potato microtuber in secondary growth process. The third is to decide whether potato microtubers are infected by a virus or bacteria in growth process. The computation for the growth density in the primary growth process uses the method of Labeling. The second and third methods use template matching based on color patterns. With the developed method using vision process, this experiment is capable of discriminating weekly growth-rate in primary growth process, 85% cognition rate in secondary process and identifying whether there are infections. Therefore, we conclude that our experimental results are capable of growth monitoring for mass production of potato microtubers.

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Growth rate and growth steps of 6H-SiC single crystals in the sublimation process

  • Kang, Seung-Min;Lim, Chang-Sung;Auh, Keun-Ho
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.11 no.4
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    • pp.166-169
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    • 2001
  • 6H-SiC bulk crystals were grown by sublimation method with different conditions in term of gaseous pressures ad source temperatures. In order to optimize the growth rate, pressure at growth period and source and substrate temperatures were investigated as experimental variables. the results were compared with each other and finally the optimum growth conditions were discussed. Furthermore the relation of the growth steps and defects formation was evaluates in the point of reducing the micropipes. Subsequently the growth steps and defects formation was evaluated in the point of reducing the micropipes. Subsequently the growth steps were observed leading to the lower step height with the lower growth rate.

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Investigation of carbon nanotube growth termination mechanism by in-situ transmission electron microscopy approaches

  • Kim, Seung Min;Jeong, Seojeong;Kim, Hwan Chul
    • Carbon letters
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    • v.14 no.4
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    • pp.228-233
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    • 2013
  • In this work, we report in-situ observations of changes in catalyst morphology, and of growth termination of individual carbon nanotubes (CNTs), by complete loss of the catalyst particle attached to it. The observations strongly support the growth-termination mechanism of CNT forests or carpets by dynamic morphological evolution of catalyst particles induced by Ostwald ripening, and sub-surface diffusion. We show that in the tip-growth mode, as well as in the base-growth mode, the growth termination of CNT by dissolution of catalyst particles is plausible. This may allow the growth termination mechanism by evolution of catalyst morphology to be applicable to not only CNT forest growth, but also to other growth methods (for example, floating-catalyst chemical vapor deposition), which do not use any supporting layer or substrate beneath a catalyst layer.

Mechanism of Growth Hormone Action : Recent Developments - A Review

  • Sodhi, R.;Rajput, Y.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.12
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    • pp.1785-1793
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    • 2001
  • The interaction of growth hormone with it's receptor results in dimerization of receptor, a feature known in action of certain cytokines. The interaction results in generation of number of signalling molecules. The involvement of Janus kinases, mitogen activated kinases, signal transduction and activator of transcription proteins, insulin like substrate, phosphatidylinositol 3-kinase, phospholipase C, protein kinase C is almost established in growth hormone action. There are still many missing links in explaining diversified activities of growth hormone. Amino acid sequence data for growth hormones and growth hormone receptors from a number of species have proved useful in understanding species specific effects of growth hormone. Complete understanding of growth hormone action can have implications in designing drugs for obtaining desired effects of growth hormone.

Efficient Procedural Modeling of Trees Based on Interactive Growth Volume Control

  • Kim, Jinmo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.9
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    • pp.2232-2245
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    • 2013
  • The present study proposes efficient procedural modeling methods for enabling the growth and creation of various trees with minimal user control. Growth volume algorithms are utilized in order to easily and effectively calculate many parameters that determine tree growth, including branch propagation. Procedural methods are designed so that users' interactive control structures can be applied to these algorithms to create unique tree models efficiently. First, through a two-line-based interactive growth volume control method, the growth information that determines the overall shape of the tree is intuitively adjusted. Thereafter, independent branch control methods designed to control individual branches are added to the growth deformation in order to enable the growth of unique trees. Whether the growth processes of desired trees can be easily and intuitively controlled by the proposed method is verified through experiments. Methods that can apply the proposed methods are also verified.

Market Access Approach to Urban Growth

  • MOON, YOON SANG
    • KDI Journal of Economic Policy
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    • v.42 no.3
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    • pp.1-32
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    • 2020
  • This paper studies urban growth in Korean cities. First, I document that population growth patterns change over time and that the current population distribution supports random urban growth. I confirm two empirical laws-Zipf's law and Gibrat's law-both of which hold in the period of 1995-2015, but do not hold in the earlier period of 1975-1995. Second, I find a systematic employment growth pattern of Korean cities in spite of the random population growth. I examine market access effects on employment growth. Market access, a geographical advantage, has a significant influence on urban employment growth. The market access effect is higher in the Seoul metropolitan area than in the rest of the country. This effect is stronger on employment growth in the manufacturing industry compared to employment growth in the service industry. These results are robust with various checks (e.g., different definitions of urban areas). The results here suggest that policymakers should consider geographical characteristics when they make policy decisions with respect to regional development.

Growth patterns of preterm infants in Korea

  • Lim, Joohee;Yoon, So Jin;Lee, Soon Min
    • Clinical and Experimental Pediatrics
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    • v.65 no.1
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    • pp.1-9
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    • 2022
  • With advancements in neonatal care and nutrition, the postnatal growth of preterm infants has improved; however, it remains an issue. Accurate assessments of growth using a standardized reference are needed to interpret the intrauterine and postnatal growth patterns of preterm infants. Growth in the earlier periods of life can contribute to later outcomes, and the refinement of postnatal growth failure is needed to optimize outcomes. Catch-up growth occurs mainly before discharge and until 24 months of age, and very low birth weight infants in Korea achieve retarded growth later in life. Knowing an infant's perinatal history, reducing morbidity rates during admission, and performing regular monitoring after discharge are required. Preterm infants with a lower birth weight or who were small for gestational age are at increased risk of poor neurodevelopmental outcomes. Furthermore, poor postnatal growth is predictive of adverse neurodevelopmental outcomes. Careful monitoring and early intervention will contribute to better development outcomes and national public health improvements.